The present invention relates generally to milling tools and, more particularly, to milling tools in which cutting inserts are secured to a toolholder by a clamping screw. The invention also relates to a clamping screw suitable for a milling tool.
In milling tools for metal removal, it is often desirable to position a plurality of cutting inserts around the periphery of the toolholder body. A typical technique of securing the inserts in pockets formed on the toolholder body is via a screw that extends through a hole in the insert and into a threaded hole in the toolholder body. Typically, the screw has an enlarged head that clamps against a surface in the hole in the insert to clamp the insert in place. The enlarged head usually includes a key grip, typically a female key grip, that can be driven by a male tightening (or removal) tool or “key”. For various reasons, it may be difficult or impossible to access the key grip on the clamping screw with the male tool. For example, due to provision of a large number of closely spaced inserts around the periphery of the toolholder, flutes in the toolholder may be configured so that there is insufficient clearance space for a tool to enter the key grip on the insert. JP 61 175313 U discloses a milling tool having a clamping screw easily accessible from the chip space of an adjacent milling insert. DE 30 21 355 A1 discloses a milling tool having a clamping screw with key grips at its ends.
It is desirable to provide a milling tool that facilitates tightening of a clamping screw even though a key grip on the clamping screw is inaccessible by a tightening tool, such as when the imaginary extension of the screw axis intersects a preceding tool portion in the tool's rotational direction.
A milling tool includes a toolholder having an insert-receiving pocket, a cutting insert having a hole provided therein, the cutting insert being disposed in the pocket, and wherein a clamping screw has a male key grip at a first end and zero or more key grips at a second end, the clamping screw extending through the hole in the cutting insert into a threaded hole in the toolholder so that threads on the clamping screw mate with threads in the threaded hole, said male key grip being remote from the cutting insert, the second end of the clamping screw comprising an enlarged head comprising a clamping surface that abuts a clamping surface in the hole of the cutting insert. A clamping screw suitable for a milling tool includes a male key grip at a first end and zero or more key grips at a second end, threads being arranged on the clamping screw between the first end and the second end, wherein the second end of the clamping screw comprises an enlarged head comprising a clamping surface.